Patent · US Expired

Compound semiconductor substrate having a hetero-junction and a field-effect transistor using the same

US5449928A · kind A · utility

12Cited by
0References
7Claims
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Assignee

Inventors

Key dates

Filing dateSep 14, 1993
Grant dateSep 12, 1995
Priority date
Expiry dateSep 14, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D62/824

Abstract

A pseudomorphic HEMT of a structure which prevents the distribution of 2DEG in the channel layer from being concentrated near the hetero-interface relative to a doping layer and which, at the same time, enables the thickness of the channel layer to which distortion is imparted to be decreased. In an n-InAlAs/InGaAs pseudomorphic structure grown on an InP substrate 1, an InGaAs spacer layer 4 having an In composition ratio smaller than that of an InGaAs channel layer 3 is inserted in an InAlAs/InGaAs hetero-interface. The InGaAs channel layer 3 has an In composition ratio of 0.80 to exhibit a high mobility. Another InAlAs buffer layer 2, spacer layer 5 and doping layer 6 have an In composition ratio of 0.52 which is in lattice-match with the substrate, and InGaAs spacer layer 4 and cap layer 7 have an In composition ratio of 0.53 which is in lattice-match with the substrate. This constitution makes it possible to control the two-dimensional electron gas and to further increase the mobility.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.